On Mon, Feb 15, 2016 at 08:58:03AM +0100, Thomas Petazzoni wrote: > diff --git a/Documentation/devicetree/bindings/dma/mv-xor-v2.txt b/Documentation/devicetree/bindings/dma/mv-xor-v2.txt > new file mode 100644 > index 0000000..0a03dcf > --- /dev/null > +++ b/Documentation/devicetree/bindings/dma/mv-xor-v2.txt > @@ -0,0 +1,19 @@ > +* Marvell XOR v2 engines > + > +Required properties: > +- compatible: Should be "marvell,mv-xor-v2" > +- reg: Should contain registers location and length (two sets) > + the first set is the DMA registers > + the second set is the global registers > +- msi-parent: Phandle to the MSI-capable interrupt controller used for > + interrupts. > + > +Example: > + > + xor0@400000 { > + compatible = "marvell,mv-xor-v2"; > + reg = <0x400000 0x1000>, > + <0x410000 0x1000>; > + msi-parent = <&gic_v2m0>; > + dma-coherent; > + }; This should be a separate patch :) > +/* DMA Engine Registers */ > +#define DMA_DESQ_BALR_OFF 0x000 > +#define DMA_DESQ_BAHR_OFF 0x004 > +#define DMA_DESQ_SIZE_OFF 0x008 > +#define DMA_DESQ_DONE_OFF 0x00C > +#define DMA_DESQ_DONE_PENDING_MASK 0x7FFF > +#define DMA_DESQ_DONE_PENDING_SHIFT 0 > +#define DMA_DESQ_DONE_READ_PTR_MASK 0x1FFF > +#define DMA_DESQ_DONE_READ_PTR_SHIFT 16 > +#define DMA_DESQ_ARATTR_OFF 0x010 > +#define DMA_DESQ_ATTR_CACHE_MASK 0x3F3F > +#define DMA_DESQ_ATTR_OUTER_SHAREABLE 0x202 > +#define DMA_DESQ_ATTR_CACHEABLE 0x3C3C > +#define DMA_IMSG_CDAT_OFF 0x014 > +#define DMA_IMSG_THRD_OFF 0x018 > +#define DMA_IMSG_THRD_MASK 0x7FFF > +#define DMA_IMSG_THRD_SHIFT 0x0 > +#define DMA_DESQ_AWATTR_OFF 0x01C > + /* Same flags as DMA_DESQ_ARATTR_OFF */ > +#define DMA_DESQ_ALLOC_OFF 0x04C > +#define DMA_DESQ_ALLOC_WRPTR_MASK 0xFFFF > +#define DMA_DESQ_ALLOC_WRPTR_SHIFT 16 > +#define DMA_IMSG_BALR_OFF 0x050 > +#define DMA_IMSG_BAHR_OFF 0x054 > +#define DMA_DESQ_CTRL_OFF 0x100 > +#define DMA_DESQ_CTRL_32B 1 > +#define DMA_DESQ_CTRL_128B 7 > +#define DMA_DESQ_STOP_OFF 0x800 > +#define DMA_DESQ_DEALLOC_OFF 0x804 > +#define DMA_DESQ_ADD_OFF 0x808 Please namespace these and others. Something like MRVL_XOR_XXX or anyother patter you like would be fine... > + > +/* XOR Global registers */ > +#define GLOB_BW_CTRL 0x4 > +#define GLOB_BW_CTRL_NUM_OSTD_RD_SHIFT 0 > +#define GLOB_BW_CTRL_NUM_OSTD_RD_VAL 64 > +#define GLOB_BW_CTRL_NUM_OSTD_WR_SHIFT 8 > +#define GLOB_BW_CTRL_NUM_OSTD_WR_VAL 8 > +#define GLOB_BW_CTRL_RD_BURST_LEN_SHIFT 12 > +#define GLOB_BW_CTRL_RD_BURST_LEN_VAL 4 > +#define GLOB_BW_CTRL_WR_BURST_LEN_SHIFT 16 > +#define GLOB_BW_CTRL_WR_BURST_LEN_VAL 4 > +#define GLOB_PAUSE 0x014 > +#define GLOB_PAUSE_AXI_TIME_DIS_VAL 0x8 > +#define GLOB_SYS_INT_CAUSE 0x200 > +#define GLOB_SYS_INT_MASK 0x204 > +#define GLOB_MEM_INT_CAUSE 0x220 > +#define GLOB_MEM_INT_MASK 0x224 > + > +#define MV_XOR_V2_MIN_DESC_SIZE 32 > +#define MV_XOR_V2_EXT_DESC_SIZE 128 > + > +#define MV_XOR_V2_DESC_RESERVED_SIZE 12 > +#define MV_XOR_V2_DESC_BUFF_D_ADDR_SIZE 12 > + > +#define MV_XOR_V2_CMD_LINE_NUM_MAX_D_BUF 8 These do look fine! > + > +/* descriptors queue size */ > +#define MV_XOR_V2_MAX_DESC_NUM 1024 Is this hardware defined? > +static void mv_xor_v2_set_data_buffers(struct mv_xor_v2_device *xor_dev, > + struct mv_xor_v2_descriptor *desc, > + dma_addr_t src, int index) > +{ > + int arr_index = ((index >> 1) * 3); > + > + /* > + * fill the buffer's addresses to the descriptor > + * The format of the buffers address for 2 sequential buffers X and X+1: space around + please. > + * First word: Buffer-DX-Address-Low[31:0] > + * Second word:Buffer-DX+1-Address-Low[31:0] > + * Third word: DX+1-Buffer-Address-High[47:32] [31:16] > + * DX-Buffer-Address-High[47:32] [15:0] > + */ > + if ((index & 0x1) == 0) { > + desc->data_buff_addr[arr_index] = lower_32_bits(src); > + > + /* Clear lower 16-bits */ > + desc->data_buff_addr[arr_index + 2] &= ~0xFFFF; > + > + /* Set them if we have a 64 bits DMA address */ > + if (IS_ENABLED(CONFIG_ARCH_DMA_ADDR_T_64BIT)) > + desc->data_buff_addr[arr_index + 2] |= > + upper_32_bits(src) & 0xFFFF; So why should it depend on how kernel is configured? > + } else { > + desc->data_buff_addr[arr_index + 1] = > + lower_32_bits(src); > + > + /* Clear upper 16-bits */ > + desc->data_buff_addr[arr_index + 2] &= ~0xFFFF0000; > + > + /* Set them if we have a 64 bits DMA address */ > + if (IS_ENABLED(CONFIG_ARCH_DMA_ADDR_T_64BIT)) > + desc->data_buff_addr[arr_index + 2] |= > + (upper_32_bits(src) & 0xFFFF) << 16; > + } > +} > + > +/* > + * Return the next available index in the DESQ. > + */ > +static inline int mv_xor_v2_get_desq_write_ptr(struct mv_xor_v2_device *xor_dev) Pls wrap with 80 chars wherever it is reasonable > +/* > + * Allocate resources for a channel > + */ > +static int mv_xor_v2_alloc_chan_resources(struct dma_chan *chan) > +{ > + /* nothing to be done here */ > + return 0; > +} No need for empty alloc > + > +/* > + * Free resources of a channel > + */ > +void mv_xor_v2_free_chan_resources(struct dma_chan *chan) > +{ > + /* nothing to be done here */ > +} and free as well :) > +static irqreturn_t mv_xor_v2_interrupt_handler(int irq, void *data) > +{ > + struct mv_xor_v2_device *xor_dev = data; > + > + /* > + * Update IMSG threshold, to disable new IMSG interrupts until > + * end of the tasklet > + */ > + mv_xor_v2_set_imsg_thrd(xor_dev, MV_XOR_V2_MAX_DESC_NUM); You don't want to check the source of interrupt? > +static dma_cookie_t > +mv_xor_v2_tx_submit(struct dma_async_tx_descriptor *tx) > +{ > + int desq_ptr; > + void *dest_hw_desc; > + dma_cookie_t cookie; > + struct mv_xor_v2_sw_desc *sw_desc = > + container_of(tx, struct mv_xor_v2_sw_desc, async_tx); > + struct mv_xor_v2_device *xor_dev = > + container_of(tx->chan, struct mv_xor_v2_device, dmachan); > + > + dev_dbg(xor_dev->dmadev.dev, > + "%s sw_desc %p: async_tx %p\n", > + __func__, sw_desc, &sw_desc->async_tx); > + > + /* assign coookie */ > + spin_lock_bh(&xor_dev->cookie_lock); > + cookie = dma_cookie_assign(tx); > + spin_unlock_bh(&xor_dev->cookie_lock); > + > + /* lock enqueue DESCQ */ > + spin_lock_bh(&xor_dev->push_lock); Why not a generic channel lock which is used in submit, issue_pending and tasklet. What is the reason for opting different locks? > + > + /* get the next available slot in the DESQ */ > + desq_ptr = mv_xor_v2_get_desq_write_ptr(xor_dev); > + > + /* copy the HW descriptor from the SW descriptor to the DESQ */ > + dest_hw_desc = ((void *)xor_dev->hw_desq_virt + cast to and away from void are not required > + (xor_dev->desc_size * desq_ptr)); > + > + memcpy(dest_hw_desc, &sw_desc->hw_desc, xor_dev->desc_size); > + > + /* update the DMA Engine with the new descriptor */ > + mv_xor_v2_add_desc_to_desq(xor_dev, 1); > + > + /* unlock enqueue DESCQ */ > + spin_unlock_bh(&xor_dev->push_lock); and if IIUC, you are pushing this to HW as well, that is not quite right if thats the case. We need to do this in issue_pending > +static struct dma_async_tx_descriptor * > +mv_xor_v2_prep_dma_xor(struct dma_chan *chan, dma_addr_t dest, dma_addr_t *src, > + unsigned int src_cnt, size_t len, unsigned long flags) > +{ > + struct mv_xor_v2_sw_desc *sw_desc; > + struct mv_xor_v2_descriptor *hw_descriptor; > + struct mv_xor_v2_device *xor_dev; > + int i; > + > + BUG_ON(src_cnt > MV_XOR_V2_CMD_LINE_NUM_MAX_D_BUF || src_cnt < 1); why BUG_ON, is the system unusable after this? > +/* > + * poll for a transaction completion > + */ > +static enum dma_status mv_xor_v2_tx_status(struct dma_chan *chan, > + dma_cookie_t cookie, struct dma_tx_state *txstate) > +{ > + /* return the transaction status */ > + return dma_cookie_status(chan, cookie, txstate); why not assign this as you status callback? > +static void mv_xor_v2_issue_pending(struct dma_chan *chan) > +{ > + struct mv_xor_v2_device *xor_dev = > + container_of(chan, struct mv_xor_v2_device, dmachan); > + > + /* Activate the channel */ > + writel(0, xor_dev->dma_base + DMA_DESQ_STOP_OFF); what if channel is already running? > +static void mv_xor_v2_tasklet(unsigned long data) > +{ > + struct mv_xor_v2_device *xor_dev = (struct mv_xor_v2_device *) data; > + int pending_ptr, num_of_pending, i; > + struct mv_xor_v2_descriptor *next_pending_hw_desc = NULL; > + struct mv_xor_v2_sw_desc *next_pending_sw_desc = NULL; > + > + dev_dbg(xor_dev->dmadev.dev, "%s %d\n", __func__, __LINE__); > + > + /* get thepending descriptors parameters */ space after the pls > +static struct platform_driver mv_xor_v2_driver = { > + .probe = mv_xor_v2_probe, > + .remove = mv_xor_v2_remove, > + .driver = { > + .owner = THIS_MODULE, I dont think we need this -- ~Vinod -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html